net: sfp: avoid EEPROM read of absent SFP module

If SFP module is not present, it is sensible to fail sfp_module_eeprom()
and sfp_module_eeprom_by_page() early to avoid excessive I2C transfers
which are garanteed to fail.

Suggested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Ivan Bornyakov <i.bornyakov@metrotek.ru>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/phy/sfp.c b/drivers/net/phy/sfp.c
index 81edc45..bf34503 100644 (file)
--- a/drivers/net/phy/sfp.c
+++ b/drivers/net/phy/sfp.c
@@ -2487,6 +2487,9 @@ static int sfp_module_eeprom(struct sfp *sfp, struct ethtool_eeprom *ee,
        unsigned int first, last, len;
        int ret;
 
+       if (!(sfp->state & SFP_F_PRESENT))
+               return -ENODEV;
+
        if (ee->len == 0)
                return -EINVAL;
 
@@ -2519,6 +2522,9 @@ static int sfp_module_eeprom_by_page(struct sfp *sfp,
                                     const struct ethtool_module_eeprom *page,
                                     struct netlink_ext_ack *extack)
 {
+       if (!(sfp->state & SFP_F_PRESENT))
+               return -ENODEV;
+
        if (page->bank) {
                NL_SET_ERR_MSG(extack, "Banks not supported");
                return -EOPNOTSUPP;